RichTextBox: Memory Leak in RichTextBox due to improper (event subscription for timer) code in Telerik.Windows.Documents.Utils.DelayedExecution. 

Zooming out causes some table borders to disappear.

Selecting cells in one direction with the keyboard and then reversing the direction breaks the selection.

Please see the attached video.

I've managed to fix this by altering the source code of  method ParagraphLayoutBox.MeasureOverride and hope it doesn't cause other problems.

Memory leak due to content controls and caret events. 

Selection is not correct after calling the MeasureAndArrangeInDefaultSize and using the flow layout mode. This happens when the document is already set to the RichTextBox.

 Performing an undo operation on a content control that cannot be deleted causes wrong behavior.

In Narrator scan mode RichTextBox is not accessible.

Improve the speed of the delete operation when deleting content in large documents.

Clicking at the end of the line does not select the last word of the line, but selects the first word of the next line.

Provide API that allows setting the width of the caret.

Pasting text with multiple paragraphs into a plain text content control is still possible when IsMultiline is set to false. 

When you have a single PlainTextControl in the document you can insert another content controls in it. 

Pasting text inside a ContentControl is disabled if it is locked.

As shown in the attached video.

As shown in the attached video.

As shown in the attached video.

As shown in the attached video.

As shown in the attached video.

Btw, I was using the MS Pinyin IME.

Unsupported merge fields (NotSupportedField) are automatically updated when hosted in a header or footer. In MS Word, the fields are not updated/evaluated until you manually call their Update Field action (in the right click menu shown over the field).